Glazing unit

ABSTRACT

A glazing unit that provides desired transparency for viewing operations being carried out at elevated temperatures within a tunnel-like enclosure while preventing objectionable heat loss and protecting an observer of such operations. It includes a special mounting that permits ready installation and removal of the viewing surfaces for cleaning.

Tlnited States Patent Olson [15] 3,656,471 [451 Apr. 18,1972

[ GLAZING UNIT [72] Inventor: Albert W. Olson, Toledo, Ohio [73] Assignee: Libbey-Owens-Ford Company, Toledo,

Ohio

[22] Filed: Dec. 31, 1969 [21] Appl. No.: 889,519

[52] US. Cl... ..126/200 [51] Int. Cl ..F23n 7/00 [58] Field of Search 126/200; 1 10/179; 52/304, 399

[56] References Cited UNITED STATES PATENTS 2,264,176 11/1941 Englehart et a1 ..52/304 X 2,724,873 11/1955 Cameron ..52/399 FOREIGN PATENTS OR APPLICATIONS 8,007 1893 Great Britain ..126/200 Primary Examiner-Charles .1. Myhre Attorney-Collins and Oberlin [57] ABSTRACT A glazing unit that provides desired transparency for viewing operations being carried out at elevated temperatures within a tunnel-like enclosure while preventing objectionable heat loss and protecting an observer of such operations. It includes a special mounting that permits ready installation and removal of the viewing surfaces for cleaning.

1 Claims, 3 Drawing Figures as L ll GLAZING UNIT This invention relates broadly to glazing units to be installed in the walls of a furnace and more particularly to an improved unit of this general character that can be readily installed in and removed from a window or sight opening in a furnace wall.

An important object of the invention is to provide improved sight opening glazing units in the wall of a heat-treating furnace that will permit convenient observation of the heat treating operations while protecting the observer from the high furnace temperatures required.

Another object is the provision of a multiple sheet glazing unit of this character which includes a frame that can be readily installed in the furnace wall and which supports the transparent panels of the unit so that they can be removed for cleaning and replacement when necessary.

Other objects and advantages will become apparent during the course of the following description, when considered in connection with the accompanying drawings, wherein like numerals are employed to designate like parts throughout.

In the drawing:

FIG. 1 is fragmentary side elevation of a heat-treating furnace wherein glazing units, constructed in accordance with this invention, are mounted in superimposed sight openings in a wall thereof;

FIG. 2 is a perspective view, partly in cross-section, of one of the glazing units; and

FIG. 3 is a horizontal section view taken on the plane of line 3-3 of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION As herein contemplated, the glazing units of this invention are adapted to provide transparent viewing areas through the wall of a furnace enclosure wherein many forms of production operations can be carried out in an atmosphere of relatively high temperatures. Consequently such a glazing unit, while affording an adequate observation area, must be constructed to protect an observer from exposure to the high temperature while preventing the loss of such temperature or entry of relatively cooler air. Moreover, when the operations being carried out within the furnace cause the atmosphere therein to be contaminated by exhausted fumes or other residual matter, it is natural to expect that transparency of the glazing unit will gradually be impaired.

Accordingly, this invention provides a glazing unit that can be installed or removed with a minimum amount of handling and from which the transparent panels can be removed and replaced for cleaning with the same convenience. Such expediency of handling is further made possible by employing two or more glazing units of smaller dimension instead of employing a single large unit to glaze a given opening or viewing area in a furnace wall.

With this in mind and, by way of example only, there is illustrated in FIG. 1 of the drawing two glazing units, generally designated by the numeral 10, mounted one above the other in the wall of a furnace 11. As best shown in FIG. 2, these glazing units, which are constructed in accordance with the present invention, include a mounting casing or sash 15, a plurality of transparent glass panels 16, 17 and 18, a frame 19 for supporting the panels and a retaining member 20. Thus, the mounting sash is formed of a sheet metal material that is suitably shaped to provide a vertical wall or flange portion 22, a horizontally disposed wall portion 23, a second vertically disposed wall portion 24 and horizontal end wall portion 25. The horizontal wall portion 23 and vertical wall portion 24 provide a housing area in which the frame 19 is received.

This frame 19 is preferably formed by a bottom 27, top bar 28 and side bars 29 and 30 all having suitably mitered ends (not shown) whereby the respective bars can be assembled in substantially right-angle relation to one another. The body of each bar is formed with grooves 31 that are equally spaced apart to provide similar spacing between the panels 16, I7 and 18 when received therein. The frame er se is referably of a material that has good heat-resrstan prope res to reduce transmission of heat to the glass panels as well as afford a normally expected amount of service.

It is desirable that the glass panels 16 and 17, and at least the panel 16, possess heat-resistant characteristics, such as glass commercially available under the trademark Pyrex," thereby being less susceptible to breakage while subjected to the high temperatures within the furnace. When the bars 27, 28, 29 and 30 have been fitted around the glass panels to form the frame 19, it is placed as an integral unit within the housing area provided by the horizontal wall portion 23 and vertical wall portion 24 of the sash 15. The retaining member 20 is placed against the outwardly-directed surface of the frame and fixed in position as by means of screws or like fastenings 35 threaded into the wall portion 23.

As viewed in FIGS. 1 and 3, the glazing unit 10 is adapted to be mounted within a framing element 40, for a sight opening in the wall of the furnace 11, that is of a size and general outline to permit the sash 15 to be easily and loosely received therein. The element 40 has an outwardly-directed rectangular plate 41 that is mounted on the furnace wall (indicated in broken line in FIG. 3). A filler strip 42 of insulation material, such as asbestos, is fitted around the sash 15 which is fixed within the framing element 40 by latches 45 and bolts 46 that clamp the latches against the outwardly-directed vertical wall 22 of the sash.

It will be apparent from the above that this invention provides a remarkably simple and readily replacable unit for glazing furnace sight openings that offers many advantages over the rather complicated structures heretofore available for this purpose. More specifically with this unit the several transparent panels 16 to 18 thereof are mounted in slotted bars 27 to 30 that are carried by the metal frame 15; and this complete unit can be mounted by simply sliding it into any framed sight opening of approximately the same size and can subsequently be removed by simply sliding it out.

For example, when cleaning or replacement of the glass panels in a mounted unit becomes necessary, loosening of the bolts 46 will permit the latches 45 to release the wall portions 22 of the sash 15, whereupon the entire unit can be removed from the furnace opening; and, immediately thereafter, a similarly constructed replacement unit can be rapidly and easily installed by reversing the procedure, with a minimum amount of heat loss.

Moreover, removal of the transparent panels from a dismounted unit requires only loosening of the screws 35, sliding out of the slotted bars 27 to 30, and their removal from the panels. Thereafter, cleaned or new panels can be as readily inserted to provide an available replacement unit.

Iclaim:

l. The combination, with a heated chamber having a sight opening in a wall thereof, and a framing for said sight opening; of a transparent closure for said opening comprising an open frame, a plurality of transparent sheets arranged in spaced face to face relation with at least the innermost one being of heat-resistant glass and with a plurality of slotted blocks fitting over the edges of said sheets and substantially filling the opening in said frame, and means for retaining said sheet-slotted block assembly in said frame to close the same, said frame conforming generally in size and shape to that of said sight opening framing and comprising a generally rectangular structure each side of which includes a wall substantially perpendicular to said sheets an adjoining wall substantially parallel to said sheets and extensions on said walls at substantially right angles thereto and outwardly from said sheets with the extension on said perpendicular wall overlying said chamber wall; sealing material located between said last mentioned extension and said chamber wall; and means for clamping said sealing means between said extension and said wall. 

1. The combination, with a heated chamber having a sight opening in a wall thereof, and a framing for said sight opening; of a transparent closure for said opening comprising an open frame, a plurality of transparent sheets arranged in spaced face to face relation with at least the innermost one being of heat-resistant glass and with a plurality of slotted blocks fitting over the edges of said sheets And substantially filling the opening in said frame, and means for retaining said sheet-slotted block assembly in said frame to close the same, said frame conforming generally in size and shape to that of said sight opening framing and comprising a generally rectangular structure each side of which includes a wall substantially perpendicular to said sheets an adjoining wall substantially parallel to said sheets and extensions on said walls at substantially right angles thereto and outwardly from said sheets with the extension on said perpendicular wall overlying said chamber wall; sealing material located between said last mentioned extension and said chamber wall; and means for clamping said sealing means between said extension and said wall. 